Window sash run and balance apparatus



Sept. 8, 1964 D. J. DINSMORE WINDOW SASH RUN AND BALANCE APPARATUS Filed Feb. 21, 1962 m1 m uunw 2 Sheets-Sheet 1 Sept. 8, 1964 D. J. DINSMORE WINDOW SASH RUN AND BALANCE APPARATUS Filed Feb. 21, 1962 2 SheetsfSheet 2 lllllllllllulllmln INVENTOR. MWSQ/V J p/IVJMOPC WM W0 14 4 United States Patent 3 147,517 WINDOW SASH RUN AND BALANCE APPARATUS Dawson J. Dinsmore, Sioux Falls, 5. Dak. Filed Feb. 21, 1%2, Ser. No. 174,861 15 Claims. (Cl. 20-522) This invention relates to the field of window construction and more particularly to the field of sash guide and balance apparatus.

Heretofore, numerous attempts have been made to simplify the sash balance and run used in window construction. Generally speaking, these attempts have been confined to improving or simplifying the structure concerned with each sash balance and sash guide members rather than attempting to combine the usual apparatus for both sashes into a single structure. Furthermore, in attempting to improve the sash guide members and window balance, numerous designs have led to exposed portions containing springs and other traveling members which may become fouled with twigs, leaves, etc. Others are designated so that when the sashes are removed they are exposed to the same conditions of fouling as described above even though they may be concealed in normal operation. Another problem associated with previous sash balances has been the problem of trying to keep the force exerted by the spring constant over the entire sash run so that the window does not move much more easily at one position on the sash run than on another. Of course this problem is generally not prevalent with weights but the weights take up considerable space in the window frame.

In the sash guide and balance construction, it has also been'quite common to place a stopping block or engaging block within the channel which is used to guide the sash and upon removal of the sash from the window frame, the engaging block has a member which is forced against the walls of the channel used to guide the sash block, the result being that the side walls of the channel are scored and distorted and eventually lose their effectiveness in arresting the movement of the engaging block when the sash is removed from the guides and window frame. Other sash guide members are generally fastened to the window jambs in such a manner that it is most difficult to remove these sash guide members once they have been set in place.

Applicants invention makes use of a pair of sash guide members which are releasably fastened to the window jambs to conceal all of the spring and cable mechanism for raising and lowering the sashes with a moderate amount of pressure. Furthermore, at the upper end of the sash guide member, a shoe having slots formed therein for guiding the cables replaces the pulley of most of the sash balance mechanisms so that when the spring is extended further, the frictional forces between the shoe and cable increase to hold the sash at a predetermined position. Sash guide members are also .designed so that a central groove cooperates with a pair of engaging blocks which are connected to the spring cables and engage the window sashes so that the spring may be kept under tension at any given point of removal of the window sash from the sash guide members. Also,

the centrally disposed groove does away with the problem of having the engaging blocks ride in the same channel with the window sashes and is designed so that upon repeated engagement with the edge of the centrally disposed groove, the sides of the groove are not deformed by the mechanism. Sash guide members also contain the insulation for the space between the sash guide members and window jambs and the insulation which is resilient in nature also assists in the easy removal of the window sashes from the sash guide members. With the 3,147,517 Patented Sept. 8, 1964 ICC arrangement just described, it is quite obvious that a more economical and simplified construction has been attained which will operate more efficiently and with less maintenance troubles.

It is therefore a general object of the present invention to provide a new and improved sash guide structure for use with window frames.

It is still another object of the present invention to provide new and improved means of controlling the position of the window sashes with slidable blocks for engaging a common groove in a sash guide member.

It is yet another object of the present invention to provide improved sash guides having sash engaging blocks riding in a common groove.

It is still another object of this invention to provide new and novel means for controlling the balance between the spring force, frictional forces, and weights of the window sash.

It is still another object of this invention to provide new and improved means for combining a sash cable guide in the form of a shoe and sash guide stop.

It is yet another object of the present invention to provide sash guide members which are flexible about a central axis for easy removal of the window sash.

It is still a further object of the present invention to provide means for releasably fastening the sash guides to the window jambs.

It is yet another object of this invention to provide new and improved positive locking means cooperating with the sash guide members and spring means when a window sash is removed.

It is yet another object of the present invention to provide novel insulating means which is positioned between the sash guide members and window jambs and locates the members in operative engagement with the window sashes.

These and other objects and advantages of my invention will more fully appear from the following description, made in connection with the accompanying drawings, wherein like reference characters refer to the same or similar parts throughout the several views, and in which:

FIG. 1 is a side elevation view of the sash guide member which faces inwardly towards the center of the window showing the sash guide stop and engaging blocks;

FIG. 2 is a back side view of the sash guide member shown in FIG. 1, the viewing side facing outwardly towards the window jamb;

FIG. 3' is a cross sectional view of the sash guide member taken along a plane designated by lines 33 as shown in FIG. 2, the figure being rotated counterclockwise;

FIG. 4 is a sectional view of a window frame taken along a plane through the center of the upper sash showing the relative placement of some of the parts with respect to the window frame;

FIG. 5 is an end view of the engaging block as seen from the left side as shown in FIG. 6;

FIG. 6 is a top view of the engaging block as seen from the right side of FIG. 5;

FIG. 7 is a cross sectional view of the engaging block taken along a plane designated by lines 7-7 of FIG. 5;

FIG. 8 is a side elevation view of the engaging block as seen from a bottom view of FIG. 5;

FIG. 9 is a top view of the shoe for guiding the spring cable;

FIG. 10 is a cross sectional view of the shoe taken along a plane designated by lines 1010 and;

FIG. 11 is a sectional view of the sash guide member and engaging blocks taken about the general area where the check rails of the upper and lower sash guides meet. A sash guide member 20 is formed from aluminum or other suitable and workable material which may be readily bent or formed so that a pair of inverted channels or ridges 21 and 22 are formed longitudinally with the sash guide member and are spaced from a centrally disposed groove 23 that is in the form of a channel. Of course for some applications it may be desirable to form channel members 21 and 22 so that they are directed outwardly towards the outside of the window frame in a direction corresponding to groove or channel member 23. The groove 23 is centrally located between inverted channels 22 and 21 which in turn are located substantially an equal distance from each edge of sash guide member 20. At the edge of sash member 20 which is adjacent inverted channel 22, a right angle flange 24 is formed integrally with sash guide member 20 so that a lip extends spaced from and essentially parallel with the faces of the sash guide member 20. Flange 24 is of suflicient width to accommodate a pair of springs 25 and 26 behind sash guide member 20. In a similar manner, a right angle flange 27 is formed integrally with sash guide member 20 adjacent to inverted channel 21 and it also contains a lip portion which is substantially parallel with the guiding and running surfaces of channels 21 and 22. The width of flange 27 is approximately onehalf of that of flange 24 for reasons which will be set forth later. Situated adjacent to the edge of flange 27 and behind inverted channel or ridge 21 is a strip of insulating material 28 which extends the full length of the sash guide member. The insulating material is generally formed of a polyethylene foam or other material which is resilient in nature and yet has good insulating qualities. Insulating material 23 is generally cemented to sash guide member 20 with an adhesive (not shown) but for some applications it may be desirable to cement the surface opposite that associated with sash guide member 20 and fasten the insulating material to the window jamb. In order to releasably fasten the sash guide member 20 to its associated Window jarnb, a spring clip 29 is used which has extending portions projecting under the rearward lips of flanges 24 and 27. Clips 29 are formed from a spring like material and have a center portion which is U-shaped to engage a notch or centrally formed groove in the window jamb. Where the clips fasten under the lip of flange 27, the insulating material 28 is compressed and the clip is bent to accommodate the smaller width flange 27, so that for the most part the clip is parallel to the inwardly facing surfaces of the sash guide member. Springs 25 and 26 have their lower portions which engage the bottom of sash guide member 20 formed so that they catch the lower edge 30 of the sash guide member which is cut at a slant to lie on top of the window sill.

Situated at the top of the sash guide members 20 is a shoe 31 which is used to guide a pair of spring cables 32 and 33 which are connected to springs 25 and 26 respectively. Cable 33 enters an opening 34 which leads to a hemispherically shaped slot 35 over which cable 33 passes and the cable then emerges downwardly through an opening 36. In other words, cable 33 enters shoe 31 from the bottom and extends over a hemispherically shaped slot and then returns downwardly to an opening or hole 36. In a similar manner, cable 32 enters an opening 37 in the bottom of shoe 31 and extends over a hemispherically shaped slot 38 and emerges downwardly through a hole or opening 39 at the bottom of shoe 31. Holes 36 and 37 both open downwardly into groove or channel 23 so that cables 33 and 32 are directed downwardly inside of groove 23. Grooves 35 and 38 are formed at a slight angle with respect to the inward faces of sash guide member 20 in order that the cables may be directed from behind the sash guide member into the enclosing portion of groove or channel 23. A projection 40 of shoe 31 forms a sash stop and has a pair of slots 41 and 42 cut therein adjacent to the inwardly facing edge of shoe 31 so that slots 41 and 42 engage the inwardlymost edges 43 and 44 of groove or channel 23 respectively. That is, the centrally disposed groove is U-shaped along the sides and bottom and has a pair of top flanges extending towards each other at right angles to the sides to define an open slot 45 where the flanges 43 and 44 are formed by doubling the material back over itself. As Will be seen later, projection 40 which is somewhat cube shaped extends downwardly from the top of the sash guide member 20, a distance suflicient to stop the lower sash from engaging the trim header at the top of the Window frame before the window lock fastened to the check rails strikes the trim header.

Situated within channel 23 and extending through open slot 45 is a pair of engaging blocks 46 and 47. Engaging blocks 46 and 47 are identical to each other and each has a camming lever 48 that engages a coupling block 49 which is fastened to upper sash 51 and a coupling block 50 which is fastened to a lower sash 52.

For a more detailed description of the engaging blocks, reference is made to FIGS. 5 through 8 in which engaging block 46 is described. The engaging block may be formed from any suitable material such as nylon or other plastic materials or certain metals which will not bind when used in cooperation with the metal sash guide members 29. The engaging block 46 has a pair of parallel side slots 53 and 54 formed along the sides of the engaging block for engaging edges 43 and 44 of the centrally disposed groove or channel 23 in the sash guide members. The engaging block 46 has a central slot 55 formed at right angles to the side slots 53 and 54 and extending through the engaging block from top to bottom. The engaging block also contains a closed end bore 56 which is of larger diameter at the open end of the bore and is formed with a smaller diameter at a distance inwardly from the outside surfaces. The closed end bore 56 extends parallel to the side slots 53 and 54 to communicate with the central slot 55. An elongated opening 57 is formed at right angles to closed end bore 56 and is in communication with the lower edges of side slots 53 and 54 where the elongated opening forms an angle with the side slots. Camming lever 48 is pivotally supported within the central slot 55 by a pin (not shown) which is pressed into a hole 58 to form an axis of rotation perpendicular to the closed end bore where the camming lever 48 has an extending portion which extends beyond the end of that portion of the engaging block lying on the window sash side of edges 43 and 44 of sash guide 23. It is this extension which engages sash coupling blocks 49 and 59 as shown in FIG. 11. A cylindrically shaped engaging post 59 is positioned within the elongated opening 57 to operatively engage camming lever 48 in such a manner that post 59 is free to rotate and move within opening 57. Post 59 has a knurled outer surface for engaging the edges 43 and 44 of groove or channel member 23 by being urged to the upper edge of opening 57 by camming lever 48 in the position shown in FIG. 8. Post 59 disengages edges 43 and 44 of groove 23 upon sash coupling blocks 49 and 5t) forcing camming lever 48 to move post 59 away from slots 53 and 54 in the engaging block. To keep post 59 urged into a position which will cause the post to normally engage edges 43 and 44, a spring 60 is positioned in closed end bore 56 to engage a portion of camming lever 48 and thereby cause post 59 to be in a normally engaging position within elongated opening 57. The engaging blocks also have a pair of side grooves 61 and 62 to allow cables 32 or 33 to pass thereby or be channeled into a communicating bore 63 which also communicates with bore 56 for fastening the cable to the engaging block. Engaging block 47 for instance, has cable 33 fastened thereto and allows cable 32 to pass through its groove 62 and engage engaging block 46 Where cable 32 is knotted and tied in bore 56 so that the control of the spring tension of spring 25 is transferred to the engaging block. In order to accommodate window sashes of heavier weight than normal, loops or knots may be formed in cables 32 and 33 and merely hooked to springs 25 and 26 respectively so that the cable portions are shorter.

As'briefly described beforehand, sash coupling blocks 49 and 50 are attached to upper sash 51 and lower sash 52. Specifically, coupling block 50 is attached at the upper edge of a check rail 64 forming the upper horizontal member of lower sash 52 and coupling block 49 is at tached at the side and lowermost edge of a check rail 65 which forms the lowermost horizontal member of upper sash 51. For purposes. of clarity, the usual weather stripping found between check rails 64 and 65 has been omitted so that a better' view of engaging block 47 may be seen. It will be understood that in actual usage, weather stripping will be used between the two meeting surfaces. 9

In order to show the relative position of the different sash guide members and other apparatus with respect to a window frame, reference is made to FIG. 4 in which a window frame 66 is shown in section taken through a horizontal plane passing through the upper sash 51. A window sill 67 forms the lower portion of the window frame and is situated adjacent to the lower slanting edge 30 of window sash member 20. Extending vertically upward from the outermost portion of window sill 67 is a pair of outside trim strips 68 and moving inwardly towards the normal position the window frame would assume in a house, is a pair of blind stop members 69 which extend between the window sill 67 and a top cross member generally known as a trim header (not shown). Immediately extending inward behind the blind stop 69 is a pair of window jambs 70 which have facing sides that communicate with sash guide members 20. The sash guide members are held in place by clips 29 which engage a groove or parting bead 71 which is substantially in the center of the window jambs with the groove or parting bead extending longitudinally with the window jamb. Since blind stop' 69 extends laterally towards the center of the window, it is extended sufficiently so that sash guide members 20 are engaged at their forwardmost edges regardless of whether the narrow or wider flange engages the blind stop. It will also be noted that sash guide members 20 are turned end for end when viewed from the top.' That is, flange 24 faces outside and against blind stop 69 on the left side of the window while flange 27 engages blind stop 69 on the right side of the window. A pair of inside stops 72 are normally fastened to the facing sides of window jamb 70 and engage either flange 24 or 27 of sash guide member 20. Inside stops 72 extend longitudinally with window jarn-bs 70 and engage the flanges in somewhat the same manner as blind stop 69.

Assuming that a window is completely assembled and in a closed position as shown in FIGS. 4 and 11, it will be seen that spring 26 is almost completely extended while spring 25 is almost completely compressed or drawn together. Therefore, a maximum amount of tension is applied to cable 33 and a minimum amount of tension is applied to cable 32. Upon raising lower sash 52, engaging block 47 moves upwardly in groove or channel 23 and the upward movement of lower sash 52 is aided by the tensionon spring 26. Because engaging block 47 moves with lower sash 52, the greatest frictional force created between cable 33 connected to engaging block 47 and groove 35 of shoe 31 is created when spring 26 is fully extended and this frictional force aids in keeping lower sash 52 at any predetermined position along the pair of channels forming the sash guides. In other words, the tensile force of the springs, the frictional forces be tween the cable and the shoe as well as between the sash and guide member, and the force attributed to the weight of'the sash all combine to be in a state of equilibrium when the sash is moved to any position along the sash guide. The other spring 25 operates in the same manner with its associated cable 32 while moving through slot 38 of shoe 31 with the exception that spring 25 is extended'and the tensile force increased as'upper sash 51 is moved downwardly. Both upper sash 51 and lower sash 52 have formed in their sides, a stile 73 which rides over the inverted channel sash guides 21 and 22. As can best be seen in FIGS. 8 and 11, as long as camming lever 48 engages the appropriate sash coupling block, post 59 remains out of engagement with edges 43 and 44 of groove 23 and therefore remains free to move upwardly and downwardly.

However, when a window sash is to be removed from the window frame, it is only necessary to move it laterally to disengage the stile 73 from the corresponding sash guides. By pushing to the left on lower sash guide 52, insulating strip 28 is compressed and due to the relatively thin material from which sash guide members 20 are formed, the sash guide member 20 on the left is flexed substantially about the center of the sash guides along channel 23 and since flange 27 is of narrower width than that of flange 24 flexing along channel 23 is aided to the point where there is suflicient room to clear stile 73 with sash guide 22. By pulling the right hand side of sash guide 52 towards the inside of the house or clockwise as seen from above in FIG. 4, sash 52 may be removed and upon removal, coupling block 50. disengages camming lever 48 and due to the spring action of spring 60 in engaging block 47, post 59 is driven against the edges 43 and 44 of channel 23 to lock engaging block 47 in place. To replace the lower sash, the sash is first inserted on the left side of the window frame and again insulating strip 28 is compressed and stile 73 on the right hand side of lower sash 52 again clears sash guide 22 so that upon release of the lateral pressure the lower sash is set in operative position and upon a slight movement downward, camming lever 48 is again engaged and post 59 is disengaged with edges 43 and 44 of channel or groove 23.

In a similar manner, to remove the upper sash, it is first necessary to remove lower sash 52 as just described and then repeat the use of a lateral pressure against the upper window sash 51, except that the pressure is applied to the right side of the window to compress insulating strip 28 and allow the stile on upper sash 51 to clear and move past guide member 22.

In order to remove the sash guide members for replacement of a spring or cord if broken, it is only necessary to remove upper and lower sashes 51 and 52 respectively. This will then allow the sash guides to be re moved by pulling the same from the sash members thereby disengagingthe clips 29 from engagement with parting bead 71. Clip 29 has several sharp projections (not shown) formed outwardly from the U-shaped side pieces to engage the edge of the parting bead and therefore upon replacement, the clips can be shifted slightly in a vertical direction to engage a new portion of the parting bead. It should also be kept in mind that while the sash guides 21 and 22 are shown as inverted channels they may also be made as grooves or channels and a projecting ridge formed upon sash members 51 and 52 to accomplish the same result as just described. It should also be evident that when lower sash 52 is raised vertically, that sash coupling block 50 will engage the sash stop 40 at the top of the sash run and thereby prevent the normal sash locks from damaging the trim header.

Thus, by the structure of the present invention, it can be seen that a highly efiicient and economical sash guide member has been shown which uses a central and common groove for containing the engaging blocks which control the movementof the upper and lower sashes. It will also be seen that a highly desirable construction has been achieved wherein all of the moving parts are enclosed so as not to become fouled by leaves or twigs or other materials which might be blown into the window frame. Furthermore, the use of the' shoe at the top of the sash guide member provides a means for controlling the force balance between the spring force, frictional forces and weight of the windowsash. The use of the insulating material in the present structure is such that it serves a dual purpose in providing insulation'between' the window jambs and the sash guide member as well as offering resistance to the sash guide member to keep it in place against the edge of the upper and lower window sashes but is still compressible so that the sashes may be removed from the window frame. In fact, the sash guide with its central groove construction, enhances easy flexing about the central groove so that the sashes may be easily removed or replaced and the flexing is further enhanced by having one flange of the member of lesser width than the other to further aid in removal and replacement of the sashes. A positive locking feature is found in the engaging blocks so that upon removal of the sashes the spring is held under tension in its same position as that when the window sashes are in place.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the parts without departing from the scope of my invention which consists of the matter shown and described herein and set forth in the appended claims.

I claim:

1. Window sash raising and lowering apparatus adapted to be used in window construction comprising:

(a) a pair of sash guide members, each having a longitudinal centrally disposed groove and a pair of channels forming first and second sash guides running parallel to said groove;

(b) a first and second sash having side's adapted to ride along said channels for guiding said sashes;

(c) first and second engaging blocks riding in each of said centrally disposed grooves where the first engaging block is in communication with said second sash and where the second engaging block is in communication with said first sash;

(d) and two pair of resilient elements, each pair having flexible cable portions connected between said pair of engaging blocks and the same end of each of said pair of sash guide members, said flexible cable portions of said resilient elements lying in said groove of each of said sash guide members so that when said first and second sashes are moved from their normal positions the tensile forces exerted by said resilient elements substantially balances the opposing forces transmitted thereto by said cable portions.

2. Window sash raising and lowering apparatus adapted to be used in window construction comprising:

(a) a window frame having a pair of window jambs with inwardly facing sides, a sill forming a lower cross piece and a trim header forming an upper cross piece, all of which are fixedly held in cooperative position;

(b) a pair of sash guide members releasably fastened to the facing sides of said window jambs, each having a longitudinal centrally disposed groove directed outwardly and a pair of inwardly directed ridges forming upper and lower sash guides running parallel to said groove;

() an upper and lower sash having stiles riding along said ridges for guiding said sashes between said trim header and said sill;

(d) a pair of engaging blocks riding in each of said centrally disposed grooves where the uppermost engaging block is in communication with said lower sash and where the lowermost engaging block is in communication with said upper sash;

(e) and two pair of resilient elements, each pair having flexible cable portions connected between said pair of engaging blocks and the same end of each of said pair of sash guide members, said flexible cable portions of said resilient elements lying in said groove of each of said sash guide members so that when said upper and lower sashes are moved from their normal positions the tensile forces exerted by said resilient elements substantially equals the opc posing forces transmitted thereto by said cable portions.

3. The invention as set forth in claim 2 including a shoe constructed and arranged to be releasably fastened to the end opposite said end to which said resilient elements are connected to each of said sash guide members, said shoe having a pair of semicircular shaped slots formed therein through which are threaded said flexible cable portions causingan increase in the tensile force of said resilient elements as said engaging blocks are moved away from said shoe. 4

4. The invention as set forth in claim 3 wherein said shoe is constructed and arranged to have formed therewith a cube shaped projection into which a pair of oppositely disposed slots have been formed so that said cube shaped projection is positioned in said centrally disposed groove to act as a sash stop and arrest the movement of said lower sash before striking the trim header.

5. The invention as set forth in claim 2 including an insulating strip of porous and resilient material, interposed between said sash guide members and the cooperating facing sides of said window jambs, said insulating strip being fastened to said sash guide member.

6. The invention as set forth in claim 2 wherein said sash guide members have right angle flanges at the most forward and rearward edges of each of said members, both of said flanges cooperating with, and extending towards said facing sides of said window jambs to enclose said pair of resilient elements.

7. The invention as set forth in claim 6 wherein one of said flanges is wider than the other on each of said sash guide members and where said wider flange is at a forward edge on one member and is at a rearward edge on the other of said sash guide members, said members flexing about said centrally disposed groove upon pressure being exerted laterally against the side of said sash riding along said ridges adjacent the flange of smallest width thereby allowing said sash to be swingingly removed from engagement with said sash guide members and said engaging blocks.

8. The invention as set forth in claim 2 wherein each of said pair of engaging blocks includes:

(a) a camming element pivotally supported within said block about an axis of rotation perpendicular to the axis of translational movement of said block while engaging one of said sashes;

(b) a cylindrically shaped engaging post operatively engaged by said .camming element and having an axis of rotation parallel to said axis of rotation of said camming element, said engaging post having a knurled outer surface for engaging an inside surface of said centrally disposed groove in a first position and disengaging said surface in a second position;

(0) and a spring urged into operable position against said block at one end and said camming element at the other end so that said engaging post grippingly engages said centrally disposed groove under spring tension in said first position when said sash is removed and disengages said groove to rotate freely in said second position when said sash rides along said ridges forming sash guides.

9. The invention as set forth in claim 2 wherein each of said pair of engaging blocks includes:

(a) a block of material having a pair of parallel side slots formed along the sides of said block for engaging the edges of said groove in said sash guide members, said block having a central slot formed at right angles to said side slots and extending therethrough, said block also containing a closed end bore extending parallel to said side slots to communicate with said central slot, and an elongated opening formed at right angles to said closed end bore in communication with said side slots, said elongated opening forming an angle to said side slots;

(b) a camming lever pivotally supported within said central slot about an axis of rotation perpendicular to said closed end bore and having an extending portion for engaging one of said sashes;

(c) a cylindrically shaped engaging post positioned Within said elongated opening to operatively engage said camming lever so that said post is free to rotate and move within said opening, said post having a knurled outer surface for engaging the edges of said centrally disposed groove in a first position and disengaging the edges thereof in a second position;

(d) and a spring urged into operable position in said bore to engage said camming lever so that said engaging post grippingly engages the edges of said centrally disposed groove under spring tension in said first position when said sash is removed and dissaid second position when said sash rides along said ridges forming sash guides.

10. The invention as set forth in claim 2 wherein sai centrally disposed groove is U-shaped along the sides and bottom and has a pair of top flanges extending toward each other at right'angles to said sides defining an open slot through which a portion of each of said engaging blocks projects, said top flanges being formed by doubling the material forming said sash guide members back over itself.

11. A window sash balance and selectively engageable connecting apparatus for connecting the force transmitting element in the sash balance to a movable member which is adapted to be selectively locked against movement keeping the force transmitting element in an actuated state upon the normally engaging slidable sash being removed from its window frame, said apparatus comprising:

(a) a sash guide member releasably fastened to the sides of the window frame having a longitudinal centrally disposed groove directed outwardly and a pair of channels forming two sash guides running parallel to said groove in guiding relationship with the corresponding sash;

(b) and an engaging block riding in said centrally disposed groove and being connected to the force transmitting element, said engaging block being in releas able communication with its corresponding sash so that upon removal of the sash from the window frame said engaging block is locked against movement and upon replacement of the sash in the window frame said engaging block is free to move in said centrally disposed groove.

12. Window sash raising and lowering apparatus adapted to be used in window construction comprising:

(a) a window frame having a pair of window jambs with inwardly facing sides, a sill forming a lower cross piece and a trim header forming an upper cross F engages the edges of said groove to rotate freely in piece, all of which are fixedly held in cooperative position;

i (b) a pair of sash guide members releasably fastened L to the facing sides of said window jambs, each having a pair of channels forming first and second sash guides running parallel to said window jambs, said members having right angle flanges at the most forward and rearward edges of each of said members I Where one of said flanges is wider than the other on each of said sash guide members and where said 3 wider flange is at a forward edge on one member and is at a rearward edge on the other of said members;

() an insulating strip of porous and resilient material, interposed between said sash guide members and the cooperating facing sides of said window jambs, adjacent to the flange of smaller width;

(d) and a first and second sash having sides riding along said channels for guiding said sashes, each of said sash guide members flexing about a longitudinal axis upon pressure being applied laterally against the side of said sash riding along said channels adjacent the flange of smallest width thereby allowing said sash to be swingably removed and replaced from in engagement'with said sash guide members when said strip of porous and resilient material is sufliciently compressed to allow said sash sides to clear said channels.

13. Window sash raising and lowering apparatus adapted to be used in window construction comprising:

(a) a window frame having, a pair of window jambs with inwardly facing sides, a sill forming a lower cross piece and a trim header forming an upper cross piece, all of which are fixedly held in cooperative position;

(b) a pair of sash guide members releasably fastened to the facing sides of said window jambs, each having a pair of longitudinal ridges directed .inwardly towards each other forming upper and lower sash guides running parallel to a centrally disposed groove directed outwardly and opposite to said ridges;

(c) an upper and lower sash having stiles riding along said ridges for guiding said sashes between said trim header and said sill, said sashes having check rails formed therewith;

(d) a pair of engaging blocks riding in each of said centrally disposed grooves where the uppermost engaging block is in communication with the check rail of said lower sash and where the lowermost engaging block is in communication with the check rail of said upper sash, each of said engaging blocks having locking elements for gripping said groove and arresting movement With respect thereto when disengaging said respective check rail;

(e) and two pair of spring elements, each pair having a flexible cable connected thereto between said pair of engaging blocks and the same end of each of said pair of sash guide members, said flexible cable lying in said groove of each of said sash guide members, so that when said upper and lower sashes are moved from their normal positions the tensile forces exerted by said spring elements substantially balances the opposing forces transmitted thereto by said cable portions.

14. Window sash raising and lowering apparatus adapted to be used in window construction comprising:

(a) a window frame having, a pair of window jambs with inwardly facing sides, a sill forming a lower cross piece and a trim header forming an upper cross piece, all of which are fixedly held in cooperative position;

(b) a pair of sash guide members releasably fastened to the facing sides of said window jambs each having a pair of longitudinal ridges directed inwardly to wards each other forming upper and lower sash guides running parallel to a centrally disposed groove directed outwardly and opposite to said ridges;

(c) a shoe releasably fastened to the end of each of said sash guide members adjacent the trim header, said shoe having a pair of semicircular shaped slots formed therein opening towards the sill;

(d) an upper and lower sash having stiles riding along said ridges for guiding said sashes between said trim header and said sill, said sashes having check rails formed therewith;

(e) a pair of engaging blocks riding in each of said centrally disposed grooves where the uppermost engaging block is in communication with the check rail of said lower sash and where the lowermost engaging block is in communication with the check rail of said upper sash, each of said engaging blocks having side grooves formed therealong and having locking elements gripping said groove and arresting movement with respect thereto when disengaging said re spective check rail;

(1) two pair of spring elements lying between said sash guide members and the window jambs and being connected to said members at the ends adjacent the sill;

(g) and a pair of flexible cables fastened to the free ends of each pair of said spring elements connected to each of said sash guide members and extending through the openings and semicircular shaped slots in said shoes to be connected at the other ends to said pair of engaging blocks, both cables lying in said centrally disposed groove of said sash guide member and one of which passes freely through one of the side grooves of one of said engaging blocks, so that when said upper and lower sashes are moved from their normal positions the tensile forces exerted by said spring elements substantially balances the weight of said sashes plus the frictional forces between said sashes and sash guide members, and between said 7 cables and shoe."

15. A window sash assembly comprising a longitudinal guide member engaging and guiding one end of a window sash in its movement therealong, a sash engaged by said guide member in guiding relation for movement of said sash longitudinally of said guide member, a shoe element carried by said guide member adjacent one end thereof, elastic resilient means connected to said guide member, and a cable element havingone end portion thereof connected to said sash and its other end portion connected to said means in' tensioned relation and having intermediate portions thereof passing across said shoe element while under such tension, the force of said resilient means, the frictional forces between said cable element and said shoe element as Well as between said sash and said guide member, and the force attributed to the weight of said sash all combined to be in a state of equilibrium upon said sash being moved to any position along said guide member. 1

References Cited in the file of this patent UNITED STAT ES PATENTS 2,883,715 

11. A WINDOW SASH BALANCE AND SELECTIVELY ENGAGEABLE CONNECTING APPARATUS FOR CONNECTING THE FORCE TRANSMITTING ELEMENT IN THE SASH BALANCE TO A MOVABLE MEMBER WHICH IS ADAPTED TO BE SELECTIVELY LOCKED AGAINST MOVEMENT KEEPING THE FORCE TRANSMITTING ELEMENT IN AN ACTUATED STATE UPON THE NORMALLY ENGAGING SLIDABLE SASH BEING REMOVED FROM ITS WINDOW FRAME, SAID APPARATUS COMPRISING: (A) A SASH GUIDE MEMBER RELEASABLY FASTENED TO THE SIDES OF THE WINDOW FRAME HAVING A LONGITUDINAL CENTRALLY DISPOSED GROOVE DIRECTED OUTWARDLY AND A PAIR OF CHANNELS FORMING TWO SASH GUIDES RUNNING PARALLEL TO SAID GROOVE IN GUIDING RELATIONSHIP WITH THE CORRESPONDING SASH; (B) AND AN ENGAGING BLOCK RIDING IN SAID CENTRALLY DISPOSED GROOVE AND BEING CONNECTED TO THE FORCE TRANSMITTING ELEMENT, SAID ENGAGING BLOCK BEING IN RELEASABLE COMMUNICATION WITH ITS CORRESPONDING SASH SO THAT UPON REMOVAL OF THE SASH FROM THE WINDOW FRAME SAID ENGAGING BLOCK IS LOCKED AGAINST MOVEMENT AND UPON REPLACEMENT OF THE SASH IN THE WINDOW FRAME SAID ENGAGING BLOCK IS FREE TO MOVE IN SAID CENTRALLY DISPOSED GROOVE. 